Do The Math

The math you need to hit beyond 400 steps begs units — the minute of angle (MOA). One MOA subtends 1.047" at 100 yards. Because it’s angular, a minute spans 1/2" at 50 yards, 3" at 300. At extreme range the .047 fraction does start to matter, meaning at 1,000 yards a 6-minute correction is 63".

Windage and elevation (W/E) dials on most rifle scopes for the U.S. market have 1/4-minute graduations, though some target scopes feature 1/8-minute clicks while “dangerous-game” scopes 1/2-minute. In Europe the adjustments are typically metric, with each click being 1 cm at 100 meters, or 0.36" at 100 yards. Rotation is also opposite of stateside dials.

Minutes apply to reticles as well. During my youth, T.K. “Tackhole” Lee installed dots on web strands from black widow spiders. In 4x scopes hunters liked 3-minute dots (.008 in diameter!) while powerful target scopes got tiny 1/8-minute dots. Red-dot sights and dangerous-game scopes now sport dots as big as 6 MOA — quick to paste on testy buffalo, lest hoof-prints sully your safari shirt.